Re: [Gcl-devel] address@hidden: Re: lstat]

[Camm Maguire]

Greetings!

OK, I was wrong, thankfully.

Building acl2h against the gcl installed at ut gives the following times
for soultions1.lisp:

; 534.05 seconds realtime,
; 514.10 seconds runtime, 9.27 seconds child runtime,
; 4.36 seconds systime, 2.90 seconds child systime.

(thanks for the extended times, BTW!)

I tested against two other local builds, one with C debugging only, and
another with -g -O2:

; 424.69 seconds realtime,
; 408.45 seconds runtime, 5.07 seconds child runtime,
; 4.74 seconds systime, 3.13 seconds child systime.
 
and

; 533.42 seconds realtime,
; 511.90 seconds runtime, 10.87 seconds child runtime,
; 4.50 seconds systime, 3.08 seconds child systime.

respectively.  This indicates to me a likely sensitivity to the hash
table initialization algorithm which takes place at image build time.
We already fixed a bug which had left too little randomness in our
internal table.  I thought we had solved this when we now initialize
with gmp random numbers (256 numbers 64bits wide to hash bytes with
xor).  But apparently we can still learn a thing or two about hashing,
and cannot blame gcc in this case.  I take it these are #'eq hash
tables? 

=============================================================================
seafoam$ diff -u solutions.lisp solutions1.lisp
--- solutions.lisp      2013-11-05 10:26:43.838457000 -0600
+++ solutions1.lisp     2013-11-05 13:37:11.117399000 -0600
@@ -261,7 +261,7 @@
 ; for v6-3 took about 9 minutes using ACL2(h) built on CMUCL, which is normally
 ; a much slower lisp than GCL.
 
-#+(and (not cmucl) (not gcl))
+#+(and (not cmucl))
 (def-gl-thm 1f
   :hyp (and (unsigned-byte-p 3000 x)
             (unsigned-byte-p 3000 y))
@@ -269,7 +269,7 @@
   :g-bindings (gl::auto-bindings (:mix (:nat x 3000)
                                        (:nat y 3000))))
 
-#+(and cmucl (not gcl))
+#+(and cmucl)
 (def-gl-thm 1f
   :hyp (and (unsigned-byte-p 2000 x)
             (unsigned-byte-p 2000 y))
seafoam$ 
=============================================================================

I am at a loss to account for your hour long run.  Ideas?  My build is
in /projects/acl2/camm-09-19/svn/acl2-devel/books/centaur/gl.

In any case, unless I hear back from you to the contrary, I think its
time to release 2.6.10.

Take care,
-- 
Camm Maguire                                        address@hidden
==========================================================================
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah